Working with dates in JavaScript requires understanding the Date object and its quirks. Here's a comprehensive guide.
Creating Dates#
Getting Date Components#
Setting Date Components#
Formatting Dates#
Custom Formatting#
Date Arithmetic#
Comparing Dates#
Start/End of Period#
Parsing Dates#
Timezone Handling#
Best Practices#
Creation:
✓ Use ISO 8601 strings
✓ Use Date.UTC for UTC dates
✓ Validate parsed dates
✓ Remember months are 0-indexed
Formatting:
✓ Use Intl.DateTimeFormat
✓ Store dates in UTC
✓ Display in user's timezone
✓ Use ISO for APIs
Manipulation:
✓ Create new Date objects
✓ Handle month overflow
✓ Use UTC for calculations
✓ Consider timezone differences
Avoid:
✗ Parsing ambiguous formats
✗ Mutating date objects
✗ Ignoring timezones
✗ Using deprecated methods
Conclusion#
JavaScript's Date object has quirks (0-indexed months, mutable methods) but is powerful when used correctly. Use ISO 8601 strings for parsing, Intl.DateTimeFormat for locale-aware formatting, and always consider timezones when storing and displaying dates. For complex date manipulation, consider libraries like date-fns or Luxon, but the native Date API handles most common cases effectively.